Haven't used it, but I see that it was already referred back to metalmaster (takeshi kuroda) instead of japan woodworker. JWW has a reputation among wwers as having really high prices, always good to look elsewhere.

Sintered diamond stone, though, figure unless you know you want sintered diamond for something (instead of cheap electroplate diamond like you can get everywhere), there's no great reason to dump the dollars.

I remember a vendor telling me a while ago that one of the sintered stones (might not be this one) is an interesting proposition if it gets out of flat because some of them aren't too easy to flatten.